Dust and fume sampler



T. A. WALSH May 4, 1937.

DUS T AND FUME SAMPLER Filed Dec. ll, 1935 INVENTOR 'ThomasA Wa Sh BY f M @www WITNESSE- MJ??- ATTO R N E YS,

Patented May 4, 1937 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to a device for use in testing the dust, fume and mist content of air in industrial, manufacturing and commercial plants, factories and other occupational areas.

The principal object of the invention is the provision of a device of the indicated character which is simple, inexpensive and effectual, and by Virtue of which hazards and dangers with regard to occupational diseases may be reliably determined by simple procedure according to microsoopic and colorimetrio standards.

The nature of the invention and its distinguishing features and advantages will appear when the following specification is read in connection with the accompanying drawing in which- Fig. 1 is a central longitudinal section of a device embodying features of the invention for use in testing or determining the dust mcrobic content of air, portions of the device being broken away.

Fig. 2 is a section taken on the line 2-2 of Fig. 1.

The device illustrated in the drawing for testing or determining the dust or microbic content of air includes a suitable collector of the matter to be examined. In the present instance the collector is a pump consisting of a cylinder I0 open at one end, and its other end having a removable cap II. A plunger I2 is movable in the cylinder l0. A rod I3 is connected with the plunger I2 and projects outwardly through the cap Il, and the outer end of said rod I3 has a manipulating knob I4. The rod I3 has suitable graduations I 5. The device also includes a tube I6 equal in diameter to the cylinder I0. The upper end of the tube I6 is enlarged to provide coupling means Il. A frusta-conical element I8 is secured within the tube I6 intermediate the ends thereof, which serves as a nozzle. The tube I 6 has transverse slots I9 on the opposite sides thereof at the discharge or outlet end of the nozzle I8. The slots I9 receive a slide 2 of suitable form so as to be disposed crosswise of the tube I6 in proximity to the discharge or outlet end of the nozzle I8. A definite area of the slide is prepared with suitable adhesive substance to hold the dust or microbic particles when delivered thereto. The width of the slots I9 is greater than the thickness of the slide 20 with its adhesive coating so as not to remove the adhesive when inserting the slide,

and also to allow the escape of air from the nozzle I8.

The procedure for making the test is as follows. The plunger I2 is drawn inwardly of the cylinder I8 by pulling on the knob I4, to take in or collect a sample of the air to be tested for dust or other microbio content. A slide 20 is extended in the slots I9 to be disposed crosswise of the tube I6.

' The open end of the cylinder I0 is engaged with the coupling means Il so as to bring the tube I6 in axial alinement with the cylinder I0. The device in upright position is allowed to stand a suitable length of time, which may be ten minutes for instance. The knob I4 is then manipulated to move the plunger I2 downwardly one graduation at a time at suitable intervals to cause the natural precipitation of dust particles or microbic matter, if any, on the slide, it being apparent that the air is somewhat compressed by the nozzle I8 in the movement of the plunger I2 toward said nozzle. The slide 20 may then be removed and the examination completed according to the desired standards and capacity of the various parts of the device.

I claim:

1. A device of the character described comprising a cylinder open at one end, a plunger movable in the cylinder, a tube detachably engageable with the open end of the cylinder to communicate therewith, a nozzle within the tube forming a restricted passage in continuation of the interior thereof, said tube having aligned slots in opposite walls, and a specimen slide positioned in the slots and located across the end 0f the nozzle.

2. A device of the character described comprising a cylinder open at one end, a plunger movable in the cylinder, a tube detachably engageable with the open end of the cylinder to communicate therewith, a nozzle within the tube forming a restricted passage in continuation of the interior thereof, said tube having aligned slots in opposite walls, a specimen slide positioned in the slots and located across the end of the nozzle, a rod fixed to the plunger and. projecting through the end of the cylinder, and graduations on the rod indicating step-by-step movements of the rod and plunger in discharging the contents of the cylinder against the specimen slide.

THOMAS A. WALSH. 

